A cordless telephone arranged for operation in a frequency hopping system includes multiple portable units configured for operation with a base unit and with each other by having the base unit pseudo randomly select from a plurality of communication channels available in the frequency hopping system a different starting channel for each one of the portable units. Each portable unit then provides initial communications with the base unit over the selected starting channel of the portable unit. For maintaining communications during a frequency hopping cycle between a portable unit and the base unit, the portable unit and base unit both generate a set of communication channels from the starting channel assigned to the portable unit for subsequent use in communicating over the radio frequency link. Each of the portable units is configured for operation with the base unit and with each other during a registration procedure. Information indicative of the starting channel for each portable unit and also a security code is transmitted to each of the portable units from the base unit during this registration procedure and on a predetermined communication channel at a radiated energy level well below the level normally used for normal communications.
A method for secure registration of a access device (400) having a receiver (418) and a transmitter (420) transmitting at an operational RF power level with a base station (200) having a receiver (218) and a transmitter (216) in which the base station reduces its operational RF power level to a registration RF power level and transmits a registration invitation message (610) to an access device (400), wherein the base station (200) after receiving a registration response message (614) from the access device (400) restores its power level to the operational RF power level.
A decline in effective data transmission speed and interference between adjacent channels are prevented in a wireless telecommunication system. A hopping pattern used in direct communication between wireless telecommunication terminals is stored in the wireless telecommunication terminal, and communication is performed upon synchronizing a hopping pattern used in communication via a main unit and the hopping pattern used in direct communication between wireless telecommunication terminals.
The invention relates to a registration method used for registering at least one dual mode mobile station (MMS) with an associated private base station (DBS). The private base station is connected to the public telephone network (PSTN, ISDN) and uses, for transmission and reception, frequencies which are close to or identical to those used in a cellular radio system. The dual mode mobile station can operate either in "cordless" mode, used to communicate via said private base station, or in "cellular" mode, used to communicate via base stations (BTS) within the cellular radio system. Registration of the dual mode mobile station with the private base station constitutes a preliminary stage enabling the operation of the dual mode mobile station in "cordless" mode, whereby, following each incoming or outgoing call, a conversation can be established between the dual mode mobile station and other telephone equipment, via the private base station. According to the invention, the registration method consists in interchanging signals in accordance with a preset protocol based on a preset frequency hopping law, determining the frequency over which each signal is to be transmitted, and on a preset uplink start-up frequency, over which the dual mode mobile station transmits the first signal. The frequency hopping law and the uplink start-up frequency being specific to, and known by, the dual mode mobile station and associated private base station.
A satellite network communication system in which a plurality of subscriber handset terminals communicate with a ground hub station on traffic frequency channels using spread spectrum orthogonal CDMA transmissions. The hub station includes a control generator for generating a net entry control channel for communicating synchronization correction signals (timing, frequency and power) to subscriber handset terminals and a return link receiver. Each subscriber handset terminal has a subscriber unit control channel receiver for receiving the control channel synchronization correction signals and a subscriber unit return link transmitter connected to receive the synchronization correction signals so that signals from all subscriber handset terminals arrive at the hub station in time, power and frequency synchronism. The subscriber unit return link transmitter includes frequency hopped spread spectrum carrier such that none of the signals occupies the same frequency bin at the same time. The net entry control channel transmits small time and frequency correction signals to each of the plurality of subscriber handset terminals.
A radiotelephone system (100) includes a radiotelephone (102) and a central device (104) that communicate via radio frequency (RF) signals. The radiotelephone (102) includes a user interface (114) which permits the user to request a channel change by the central device. A signal is communicated to the user if a channel change is denied. A channel scan can be conducted by the radiotelephone to identify a new channel.
